Various industrial and commercial cutting and welding systems (e.g., electric arc welders) are generally well known. These systems conventionally include a cutting or welding arc torch and a cutting or welding power source electrically connected to the torch for supplying electric power thereto. These cutting or welding systems, for example, include electroslag or stick electrode welders, Metal-Inert Gas ("MIG") welders, and Tungsten-Inert Gas ("TIG") welders and include manual and automated cutting or welding systems. For example, in a conventional automated cutting or welding system, one or more arc torches (e.g., cutting torch, welding torch, plasma arc torch) are often supported on a frame bridge and carriage system. A drive, i.e., motor, moves the arc torches along X-Y-Z coordinates during the cutting or welding of a workpiece positioned beneath the torch. A controller (e.g., preferably including a microprocessor), which usually includes a numerical control operating system, provides precise control over the position, movement, and acceleration of the torch to enable precision cutting or welding of the workpiece.
During initial setup for system operation, the system operator preferably presets the amount of cutting or welding current and the amount of gas and water flow into the torch. During system operation, for example, the power source generates a cutting or welding current to an electrode of the torch, a flow of gas is generated between the electrode and a nozzle assembly of the torch, and an electrical arc is generated extending from the electrode through a bore of a nozzle assembly of the torch into contact with a workpiece positioned beneath the nozzle assembly. The operator then manually adjusts the cutting or welding current to compensate for load changes which occur through process parameter changes such as changes in plate thickness, changes in plasma gas flow, changes in the distance from the plate to the torch, and changes in the gas and water flows into the torch.
Additionally, in such cutting or welding systems, the power source, for example, may conventionally include an input line which is connected to a conventional external supply of electric power, such as household or industrial alternating current. The power source also includes two terminals at the output side to assist in forming the cutting or welding arc. One of the terminals is connected to the welding or cutting torch, and the other terminal is connected to the workpiece to complete or close a circuit with the power source.
There is a need, however, to provide more data about the status of the various control signals such as the status of power phases (e.g., effective and inexpensive phase loss detection), more digital controls for various operations, and more simplified and less expensive controls of cutting or welding systems.